Television receiver capable of enlarging and compressing image

Description

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

[0001] The present invention relates to a digital processing of video signal and in particular to an image compressing and enlarging circuitry which is capable of displaying an image on a screen without giving disparity feeling by compressing and enlarging an image to a desired size to match the aspect ratio of the screen of a display even if the aspect ratio of the image obtained by a video signal is different from the aspect ratio of the screen of the display.

DESCRIPTION OF THE RELATED ART

[0002] Test broadcasting of high definition TV has started since 1991 in Japan and the home TV sets with a screen having an aspect ratio of 16:9 has begun to be spread. Matching of the TV sets including a screen having an aspect ratio of 16:9 with the conventional TV broad casting is a critical factor of prevailing. It is a great problem how the aspect ratio of the image of the broadcast is changed into 16:9. If an image having movie size which is commonly found in a number of recent movie software packages, that is, so-called letter box type image (the aspect ratios of the image are various) in which the aspect ratio of the whole image is 4:3 and there are blanking areas on upper and lower sides of a screen is displayed on a display with a screen having an aspect ratio of 16:9, an aspect ratio which is approximate to 16:9 could be obtained by enlarging the image in a vertical direction. Therefore, enlargement of images in a vertical direction has become an critical technology.

[0003] JP-A-1-194784 discloses a combined method including a method of adapting an image having an aspect ratio of 4:3 onto a screen having an aspect ratio of 16:9 by changing the write frequency of a line memory and the read frequency thereof to compress the image in a horizontal direction and a method of enlarging the image in a vertical direction by changing the amplitude of an output of the deflecting circuit for cutting the upper and lower areas of the image.

[0004] JP-A-3-11891 discloses a technology for enlarging an image in a vertical direction by digital signal processing. The proposed circuit configuration for interpolating scanning lines using digital signal processing to enlarge the image in a vertical direction is shown in Fig. 1.

[0005] In Fig. 1, reference numerals 201 and 202 denote input and output terminals of digitalized video signal, respectively; 203 a memory having a capacity of at least about 120 lines; 204 one-line memory; 205 and 206 ROM tables which are used for multiplying an input signal by a coefficient; 207 an adder; 208 an input terminal of a control signal for the memory 203; 209 an input terminal of a control signal for switching tables of the ROMs 205 and 206.

[0006] In the disclosed invention, the memory 203 is controlled to conduct reading of the same line plural times with a predetermined line period in accordance with a control signal from the input terminal 208. As a result of delay of a video signal by one line in the one-line memory 204, scanning line signals of adjacent upper and lower lines are supplied to the ROMs 205 and 206 and are multiplied by a coefficient in a ROM table which is selected by a control signal from the input terminal 209. A signal having a suitable center of gravity of scanning lines can be obtained from the adder 207.

[0007] The thus obtained enlarged image provide a large size picture displayed with high quality since the spacings between scanning lines when progressive scanning signals are used are less changed in comparison with a case in which the image are enlarged by changing the amplitude of the output of the deflecting circuit.

[0008] In such a manner, various techniques have been used to display an image having an aspect ratio of 4:3 on a screen having an aspect ratio of 16:9.

[0009] The above mentioned two inventions are excellent as systems for displaying an image having an aspect ratio of 4:3 on a screen having an aspect ratio of 16:9. However, letter box type image of movie software which are commonly found in recent software packages have various aspect ratios. It has become harder to change an image having various aspect ratios to an optimum size for displays having an aspect ratio of 16:9.

[0010] It is necessary to display a framing signal particularly in projector type displays when most image having an aspect ratio of 4:3 are compressed and displayed. A problem of sticking of screen or difference in luminescence decay of a phosphor may occur. Accordingly, a method of displaying no framing signal is required.

SUMMARY OF THE INVENTION

[0011] It is an object of the present invention to provide an image compressing and enlarging circuit which is capable of providing an image having a size which is matched with the aspect ratio of a screen of a display by compressing and enlarging the whole of the image to a desired size.

[0012] It is another object of the present invention to provide an image compressing and enlarging circuit which is capable of providing an image which is matched with the aspect ratio of a screen of a display by partially compressing and enlarging the image. The invention is as set out in the claims.

[0013] The above mentioned object of the present invention is accomplished by providing an image compressing and enlarging circuit comprising memory means which can be controlled on a line-by-line basis, vertical enlargement control means for controlling the memory means to read the same line plural times with a line period corresponding to a preset magnification factor; horizontal enlargement control means for controlling the memory means to read the same pixel plural times with a pixel period corresponding to the preset magnification factor; clock generating means for generating a read clock having a frequency not less than that of a write clock from the write clock of said memory means; and combining means for combining output signals from said horizontal and vertical enlargement control means with an output signal from said clock generating means.

[0014] The input video signal is written into said memory means in response to said write clock. At this time, the input video signal is managed on a line-by-line basis. On the other hand, the vertical enlargement control means determines the line period associated with reading from said memory means in accordance with a preset magnification factor by performing an operation and outputs a control signal. Similarly, the horizontal enlargement control means determines the pixel period associated with reading from said memory means in accordance with a preset magnification factor and outputs a control signal. The clock generating means generates a new clock which depends on the horizontal compression factor of the image from the input write clock. Said combining means combines the control signals from said vertical and horizontal enlargement control means with said read clock to supply the combined signal to said memory means.

[0015] If an image having an aspect ratio of 4:3 is displayed on a screen having an aspect ratio of 16:9 with a correct roundness, the frequency of a new read clock is made 4/3 times as high as that of the write clock and the magnification factor is preset 1. Then, the period which is taken to read the same line again from said on a line-by-line basis and the period which is taken to read the same pixel again on a pixel-by-pixel basis would become infinitely great. This means that the read clock will have a frequency which is 4/3 times. The image will be compressed in a horizontal direction and displayed. Therefore, an image having an aspect ratio of 4:3 will be adapted on a screen having a ratio of 16:9.

[0016] If a large magnification factor, for example, 4/3 times is preset, the period which is taken for the vertical enlargement control means to read the same line in every four lines again on a line-by-line basis is preset to 4 lines. The horizontal enlargement control means controls so that the same pixel in every four pixels is read. Accordingly, a video signal which is enlarged 4/3 times in both vertical and horizontal directions will be output. A desired magnification factor can be obtained by changing said preset value.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] 

Fig. 1 is a block diagram showing the configuration of a prior art;

Fig. 2 is a block diagram showing an of the present invention;

Fig. 3 is an explanatory view illustrating operation of the circuit of Fig. 1 and the principle of the image enlargement;

Fig. 4 is a block diagram showing the configuration of a vertical enlargement control circuit of Fig. 1;

Fig. 5 is a block diagram showing another example of the present invention;

Fig. 6 is a block diagram showing a further example of the present invention;

Fig. 7 is a block diagram showing the configuration of the vertical enlargement control circuit in an embodiment of the present invention;

Figs. 8A to 8G are explanatory views showing the applications of the embodiment of Fig. 7;

Fig. 9 is a block diagram showing a further embodiment of the present invention; and

Figs. 10A to 10D are explanatory views showing applications of the embodiment of Fig. 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Now, examples of the present invention will be described with reference to drawings.

[0019] Referring now to Fig. 2, there is shown an example of the present invention. In Fig. 2, a reference numeral 101 denotes an input terminal for digitalized video signal; 102 an output terminal for the video signal; 103 a field memory; 104 a vertical interpolating enlarging circuit; 106 a vertical interpolating circuit; 107 a horizontal interpolating enlarging circuit; 108 an image delay circuit; 109 a horizontal interpolating circuit; 110 a vertical enlarging control circuit; 111 a memory control circuit; 112 a vertical interpolation coefficient generating circuit; 113 a horizontal enlarging control circuit; 114 an image delay control circuit; 115 a horizontal interpolation coefficient generating circuit; 116 a first delay circuit; 117 a second delay circuit; 118 an input terminal for a write clock; 119 a read clock generating circuit; 120 an input terminal for a vertical enlarging ratio preset value; 121 an input terminal for a horizontal enlarging ratio presetting value and 122 a combining circuit for a memory control signal.

[0020] In Fig. 2, an image signal which is input from the input terminal 101 is controlled by a write clock from the input terminal 118 on a line-by-line basis so that it is sequentially written into the field memory 103. The clock generating circuit 119 generates a read clock having a frequency which is about 4/3 times as high as that of the input write clock and supplies it to the field memory 103 via the combining circuit 122. Accordingly, the video signal in which an image is compressed in a horizontal direction will be read from the field memory 103. The vertical enlarging control circuit 110 controls the field memory 103 via the combining circuit 122 for reading the video signal from the field memory 103 with a line period corresponding to a magnification factor. The circuit 110 prohibits writing of the one-line memory 105 included in the vertical enlarging circuit 104 with the same period to provide a line delay output of an output signal of the field memory 103. Manner of this operation is illustrated in Fig. 3.

[0021] Fig. 3 is an explanatory view showing control of a scanning line in case where the scanning line is enlarged 4/3 times in a vertical direction.

[0022] Fig. 3(b) shows an output signal of the field memory 103. The same scanning line is repeatedly read in synchronization with a line reset (Fig. 3(a)) which is conducted by the memory control circuit 111. The output signal is provided from the one-line memory 105 (Fig. 3(d)) by prohibiting writing of one line before line reset (Fig. 3(a)) in response to a write prohibiting control signal of the one-line memory 105. As a result, signals for upper and lower adjacent two scanning lines are supplied to the vertical interpolating circuit 106. That is, the signals shown in Figs. 3(b) and 3(a) are necessarily signals for adjacent scanning lines.

[0023] The vertical interpolating circuit 106 generates a scanning line signal by an interpolating operation (Fig. 3(e)) in accordance with a control signal from the vertical enlarging control circuit 110.

[0024] Configuration of the vertical enlarging control circuit 110 is shown in Fig. 4. In Fig. 4, a reference numeral 120 denotes an input terminal for an enlargement preset value which is determined in accordance with the magnification factor; 402 an output terminal for an interpolation coefficient; 403 an output terminal for a memory control signal; 402 an input terminal for a pulse having one line period; 405 an adder for adding the interpolation coefficient to the magnification factor preset value input from the input terminal 120; 406 a latch circuit for an output signal of the adder 405; 407 a latch circuit for a carry out signal of the adder 405.

[0025] This circuit configuration designed for 8 bits of the output interpolation coefficient. A new interpolation coefficient in each line can be serially obtained by repeatedly adding the magnification factor preset value with the fed back interpolation coefficient in the adder 405 in accordance with the pulse input from the input terminal 404. At this time, the carry signal for the adder 405 will become a memory control signal for repeatedly reading the same line in the field memory 108. In case of 8 bit system, the relation between the preset value X of the magnification factor and the actual magnification factor Z can be represented by the formula as follows:

[0026] As is apparent from the above mentioned formula, theoretically desired magnification factor can be obtained by increasing the bit precision.

[0027] On the other hand, the scanning line will become a signal having a gravity center in a position of Fig. 3(g) relative to the input video signal shown in Fig. 3(f) (video signal input from the input terminal 101). By displaying this signal in position of Fig. 3(h) of the actual scanning line, a video signal representing an image which is enlarged in a vertical direction can be obtained.

[0028] Enlargement in a horizontal direction can be achieved in the same manner as the enlargement in a vertical direction. A delay control signal which is generated by the horizontal enlargement control circuit 113 is fed to the field memory 103 via the combining circuit 122. The field memory is controlled to read the same pixel therefrom again with a period corresponding to the magnification factor in response to the delay control signal so that a video signal representing an image which is enlarged in a horizontal direction is obtained. The horizontal enlarging circuit 107 conducts a horizontal interpolation in accordance with a control signal from the horizontal enlargement control circuit 113 to provide a video signal representing an image which is enlarged in a horizontal direction and balanced in gravity center. Delay circuits 116 and 117 are inserted for adjusting the delay time between the control of the field memory 103 and the control of the pixel delay circuit 108, and the horizontal interpolation circuit 109.

[0029] Temporal compression of an image in a horizontal direction and enlargement of an image in vertical and horizontal directions to display the image having an aspect ratio of 4:3 on a screen having an aspect ratio of 16:9 by using the field memory 103 and one-line memory 105, etc. in such a manner in the present embodiment can be conducted by a simple circuit configuration. For example, use of a field memory HM 530281 manufactured by Hitachi Ltd. makes it possible to repeatedly read the same line by using a line reset function to provide a simple control.

[0030] Another example is shown in Fig. 5. In Fig. 5, a reference numeral 501 denotes a delay circuit for delaying a control signal for the field memory 103; 502 a delay circuit for an interpolation coefficient; the other components are identical with those of the embodiment of Fig. 2. The present example is different from the example of Fig. 2 only in that enlargement of an image in a vertical direction is conducted in a vertical direction after enlargement in a horizontal direction is conducted in the horizontal enlargement circuit 107. Operation of the circuit in the present example is identical with that of the embodiment of Fig. 2.

[0031] The delay periods of time of the delay circuits 116 and 117 are very shorter than those of the embodiment of Fig. 2. The scale of the circuit can be advantageously reduced. The delay circuits 501 and 502 are controlled on a line-by-line basis.. Accordingly, necessity for delay is almost eliminated by considering the timing of the control signal generation of the vertical enlargement control circuit 110. In other words, adopting of the configuration of the present embodiment provides a circuit having a smaller scale which is capable of compressing and enlarging an image in a desired manner.

[0032] A further example is shown in Fig. 6. In Fig. 6, a reference numeral 601 denotes a second horizontal enlargement control circuit having the same configuration as that of the horizontal enlargement control circuit 113. The other components are identical with those of the embodiment of Fig. 2. The present embodiment is different from the embodiment of Fig. 2 in that it includes a second horizontal enlargement control circuit 601 having similar operation as well as the horizontal enlargement control circuit 113. Operation of the circuit of the present embodiment is identical with that of the example of Fig. 2.

[0033] A first enlargement control circuit 113 controls the field memory 104 in accordance with a magnification factor present value fed from an input terminal 121 to provide a video signal representing an image which is enlarged in a horizontal direction. A second horizontal enlargement control circuit 601 is reset with a time lag which is delayed between the field memory 103 and the horizontal interpolation enlargement circuit 107 relative to the reset timing of the first horizontal enlargement control circuit 113 to provide a delay control signal for controlling the pixel delay circuit 108 in the horizontal interpolating enlarging circuit 107 and a coefficient value for controlling the horizontal interpolating circuit 109.

[0034] As a result, the delay circuits 116 and 117 which are necessary in the embodiment of Fig. 2 are eliminated. Most suitable circuit can be formed by choosing a circuit having a smaller scale from the delay circuits 116 and 117 of Fig. 2 and the second horizontal enlargement control circuit 601 in Fig. 6.

[0035] In the above mentioned examples, the whole of the image can be compressed or enlarged to a desired size in both vertical and horizontal directions by the vertical enlargement control circuit 110 and the horizontal enlargement control circuit 113. This approach is advantageous in reduction in blanking (no signal) areas on a screen when laterally elongated image such as letter box type movie image represented by the currently available video signals are displayed on a screen of display having an aspect ratio 16:9. However, for an image having a usual aspect ratio of 4:3, the area of the image which is rendered invisible on the screen by the enlargement is large. Further, for the letter box image, the right and left side areas of the image is rendered invisible by the alignment of the image with the upper and lower sides of the screen and blanking areas are formed on the upper and lower areas of the screen by the alignment of the image to the right and left sides of the screen, giving a disparity feeling. It is also reported that a sticking problem occurs on the screen.

[0036] An embodiment in which the above mentioned problems are overcome will be described with reference to Fig. 7. The present embodiment is different from the above mentioned example in that the vertical and horizontal enlargement control circuits 110 and 113 are improved.

[0037] Fig. 7 is a block diagram showing the configuration of the vertical enlargement control circuit 110.

[0038] In Fig. 7, a reference numeral 701 denotes a vertical counter for counting the number of lines on the screen; 702 a numerical value converter for converting the value or count of vertical counter 701 in accordance with a predetermined function. The other components are identical with those in Fig. 4. Since the preset value of the magnification factor from the input terminal 120 in the example of Fig. 4 can be freely converted in accordance with the presetting of the numerical value converter 702 depending upon the location on the screen, a desired area in the image can be enlarged at a desired ratio. The numerical value converter can be formed of logical circuits if the function is simple. For a complicated function, a look-up table system using ROMs, etc. may be adopted. An application in this embodiment is shown in Fig. 8.

[0039] Fig. 8(A) shows an image which is represented by an video signal of the current format and is compressed in a horizontal direction and is then displayed on a screen having an aspect ratio of 16:9. The image of the laterally elongated letter box type and its aspect ratio is presumed about 2:1. The whole of the image including blanking areas prior to compression has an aspect ratio of 4:3. Fig. 8B shows an image of Fig. 8A which is enlarged 4/3 times in both vertical and horizontal directions. The size of the image in a horizontal direction is equal to that of the screen having an aspect ratio of 16:9. However, blanking areas are left on the upper and lower side of the screen in this case as mentioned above, giving a disparity feeling.

[0040] Fig. 8C shows a function in the numerical value converter 702 shown in Fig. 7. Ordinate denotes a value (count) of the vertical counter 701 while abscissa denotes a magnification factor. This function provides a magnification factor of 4/3 in the center of the screen and in the vicinity thereof and increases the magnification factor on the upper and lower side areas of the screen and provides an average magnification factor of 3/2 in a vertical direction. Definition of such a function in the numerical value converter 702 provides an image which is displayed on a screen having an aspect ratio of 16:9 without blanking areas. Since the magnification factor in a horizontal direction is equal to that in a vertical direction in the central area on the screen, the image is displayed with a correct roundness. The roundness is changed only in the edges of screen. This hardly gives a disparity feeling for the image.

[0041] Fig. 8E shows an image which is enlarged 3/2 times in both vertical and horizontal directions. The size of the image in a vertical direction is equal to that of the screen having an aspect ratio of 16:9. Some areas of the image in a horizontal direction are lost. In this case, concept of the above mentioned numerical value converter 702 is introduced to the horizontal enlargement control circuit 113. An input signal of the numerical value converter 702 representing the count of the horizontal counter (not shown) and a function determining the magnification factor which decreases on opposite sides of the screen in a horizontal direction will be chosen. If the average magnification factor in a horizontal direction is preset to 4/3 times, the whole of the image can be displayed on a screen having an aspect ratio of 16:9 as shown in Fig. 8G. Also in this case, the image is distorted only at the opposite side areas of the screen in a horizontal direction, giving almost no disparity feeling.

[0042] In such a manner, the image can be partially compressed and enlarged by combination of the numerical value converter 702 shown in Fig. 7 with a circuit which is capable of enlarging the image shown in Fig. 2 to a desired size in the present embodiment. Accordingly, an image having an aspect ratio of 4:3 or letter box size image can be displayed on the screen having an aspect ratio of 16:9 without giving disparity feeling.

[0043] A further embodiment of the present invention is shown in Fig. 9. In Fig. 9, a reference numeral 901 denotes an input terminal of video signal; 902 a display including a screen having an aspect ratio of 4:3; 903 an image processing circuit for conducting signal processing for input video signal such as Y/C separation and sending the processed signal to the display 902; 904 a synchronization processing circuit for taking a synchronization signal from a video signal; 905 a mode presetting circuit for presetting the enlargement/compression factor of the video signal; 906 a vertical deflection circuit for outputting a vertical deflecting current for driving the display 902 in accordance with a mode specified by the mode presetting circuit 905 from an output signal of the synchronization processing circuit; 907 a horizontal deflection circuit for outputting a horizontal deflecting current for driving the display 902 in accordance with a mode specified by the mode presetting circuit 905 from the output signal of the synchronization processing circuit 904; 908 and 909 first and second deflecting current correcting circuits which correct the deflecting current outputs of the vertical and horizontal deflecting circuits 906 and 907, respectively; and 910 a high voltage generating circuit.

[0044] The present embodiment is different from the above mentioned examples and embodiments in that partial compression and enlargement of image is conducted by the deflection circuits and the deflection current correcting circuit. The vertical deflection circuit 906 generates a vertical saw-tooth wave for driving the display 902 in accordance with a vertical deflecting pulse from the synchronization processing circuit 904. Similarly, the horizontal deflection circuit 907 generates a horizontal saw-tooth wave for driving the display 902 in accordance with a horizontal deflecting pulse from the synchronization processing circuit 904. At this time, the vertical and horizontal deflection circuits 906 and 907 change the gradient and the phase of the generated saw-tooth wave. Accordingly, the whole of the image is enlarged in vertical and horizontal directions.

[0045] On the other hand, the first and second deflection current correcting circuits 906 and 909 correct the operation of the vertical and horizontal deflection circuits 906 and 907, respectively to give partial distortion to the saw-tooth wave. This correction partially changes the gradient of the saw-tooth wave so that the image has an enlargement/compression factor which changes depending upon the location on the screen.

[0046] The present embodiment is particularly effective for displaying a letter box type image on a screen having an aspect ratio of 4:3. An application of the embodiment is shown in Fig. 10.

[0047] Fig. 10A shows a letter box type image which is displayed on a screen having an aspect ratio of 4:3. Letter box type displays will be adopted in the second generation EDTV systems and are expected to become more popular. In the second generation EDTV systems, high definition information is displayed in upper and lower blanking areas on the screen, it is considered that slight artificiality remains on the screen having an aspect ratio of 4:3. Fig. 10B shows a scheme for reducing the blanking areas by using the vertical and horizontal deflection circuits 906 and 907 to enlarge the whole of image in vertical and horizontal directions. However, there remains a problem that an image is not visible at the right and left side areas on the screen. Fig. 10C shows an image which is compressed by decreasing the gradient of the horizontal saw-tooth wave on both right and left side thereof by means of the second deflection current correcting circuit 909 and is enlarged by increasing the gradient of the saw tooth wave on the upper and lower sides thereof by means of the first deflection current correcting circuit 908. Accordingly, almost all necessary images can be displayed. Fig. 8D shows the distortion of the displayed image when the display method of Fig. 10C is adopted. No distortion occurs in the center area (a) of the screen and the distortion is largest at the corners (d) of the screen. It hardly matters.

[0048] The approach of the present embodiment is also effective for the case in which an image is displayed on a screen having an aspect ratio of 16:9. This approach is comparatively more simple in comparison with the enlargement/compression factor variable approach using the above mentioned digital processing and is effective for the analog type displays.

[0049] Since the whole of the image can be compressed or enlarged in order to display the image having an aspect ratio of 4:3 on a screen having a ratio of 16:9, an image which matches the aspect ratio of the screen can be obtained and the image can be displayed on the screen without giving disparity feeling.

[0050] Since the image is partially compressed and enlarged, a problem that the image is partially lost by the enlargement of the whole of the image and blanking areas are remained can be solved. An image which matches with the aspect ratio of the screen can be obtained. As a result, sticking problem can be prevented from occurring.

[0051] In any cases, the invention can be embodied with a small circuit scale.

Claims

1. A television receiver comprising:
enlargement control means (110, 113; 908, 909) for compressing or enlarging an input image by vertical and/or horizontal magnification factors, respectively, to a desired size in both vertical and/or horizontal directions, so as to match an aspect ratio of a display apparatus,
characterized in that
the enlargement control means are adapted to apply vertical and/or horizontal magnification factors which vary in different areas of the image in the vertical and horizontal directions, respectively.

2. The television receiver according to claim 1, characterized in that the horizontal and vertical enlargement means apply equal magnification factors to a central area of the image.

3. The television receiver according to one of the preceding claims, characterized in that it comprises:

memory means (103) having a storage capacity not less than a given value which is controlled with at least a line period;

clock generating means (119) for generating a read clock having a frequency not less than that of a write clock from the write clock for writing a video signal in said memory means (103) and for outputting a read clock for reading said written video signal from said memory means;

characterized in that

said enlargement control means (110) comprise vertical enlargement control means for generating and outputting a signal for controlling said memory means (103) to repeatedly read the same line with a line period depending upon a first preset value when said video signal is read from said memory means (103);

and horizontal enlargement control means (113) for generating and outputting a signal for controlling said memory means (103) to repeatedly read the same pixel from said memory means (103) with a predetermined pixel period depending upon a second preset value when said video signal is read from said memory means; and

in that it further comprises combining means (122) for combining the output signal from said vertical enlargement control means, the output signal from said horizontal enlargement control means and the read clock from said clock generating means and for supplying said memory means with a combined signal; whereby to provide a video signal representing an image which is compressed and enlarged in horizontal and vertical directions to a desired size as a video signal read from said memory means.

4. The television receiver according to claim 3, characterized in that said vertical enlargement control means (110) generates and outputs an interpolation coefficient depending upon said first preset value as well as the signal for controlling said memory means, said horizontal enlargement control means generates and outputs an interpolation coefficient depending upon said second preset value as well as the signal for controlling said memory means,

further including at the subsequent stage of said memory means (103): a line memory (104) for delaying said video signal read from said memory means by one line and outputting it, the operation of said line memory being controlled in accordance with the output signal from said vertical enlargement control means;

vertical interpolating means (106) for generating and outputting an interpolation signal in accordance with an interpolation coefficient output from said vertical enlargement control means by using said video signal read from said memory means and the output signal from said line memory;

delay means (116, 117) for delaying and outputting the signal and the interpolation coefficient output from said horizontal enlargement control means;

pixel delaying means (108) for delaying the output signal from said vertical interpolating means and for outputting it, the operation of said pixel delay means being controlled in accordance with the output signal from said delay means (116); and

horizontal interpolating means (109) for generating and outputting an interpolating signal in accordance with the interpolation coefficient output from said delay means (117) by using output signals from said vertical interpolation means and said pixel delay means.

5. The television receiver according to claim 3, characterized in that said vertical enlargement control means (110) generates and outputs an interpolation coefficient depending upon said first preset value as well as the signal for controlling said memory means, said horizontal enlargement control means (113) generates and outputs an interpolation coefficient depending upon said second preset value as well as the signal for controlling said memory means,

further including at the subsequent stage of said memory means: first delay means (116, 117) for delaying and outputting the signal and the interpolation coefficient output from said horizontal enlargement control means;

pixel delay means (108) for delaying by one pixel said video signal read from said memory means and for outputting it, the operation of said pixel delay means being controlled in accordance with an output signal from said delay means (116);

horizontal interpolating means (109) for generating and outputting an interpolating signal in accordance with the interpolation coefficient output from said first delay means (117) by using said video signal read from the memory means and the output signal from said pixel delay means;

second delay means (501, 502) for delaying and outputting the signal and the interpolation coefficient output from said vertical enlargement control means;

a line memory (105) for delaying by one line the output signal from said horizontal interpolating means, the operation of said line memory being controlled in accordance with the output signal from said second delay means (501); and

a vertical interpolating means (106) for generating and outputting an interpolation signal in accordance with the interpolation coefficient output from said second delay means (502) by using the output signals from said horizontal interpolation means and the output signal from said line memory.

6. The television receiver according to claim 3, characterized in that said vertical enlargement control means generates and outputs an interpolation coefficient depending upon said first preset value as well as the signal for controlling said memory means;

a line memory (105) for delaying said video signal read from said memory means by one line and outputting it, the operation of said line memory being controlled in accordance with the output signal from said vertical enlargement control means;

vertical interpolation means (106) for generating and outputting an interpolation signal in accordance with an interpolation coefficient output from said vertical enlargement control means by using said video signal read from said memory means and the output signal from said line memory;

delay means (116, 117) for delaying and outputting the signal and the interpolation coefficient output from said horizontal enlargement control means;

pixel delaying means (108) for delaying the output signal from said vertical interpolating means and for outputting it, the operation of said pixel delaying means being controlled in accordance with the output signal from said delay means;

second horizontal enlargement control means for generating and outputting a signal for controlling said pixel delay means at intervals of a pixel period corresponding to said second preset value and for generating and outputting an interpolation coefficient corresponding to said second preset value; and

horizontal interpolating means (109) for generating and outputting an interpolating signal in accordance with the interpolation coefficient output from said delay means by using output signals from said vertical interpolating means and said pixel delay means.

7. The television receiver according to claim 4, 5 or 6, characterized in that said vertical enlargement control means comprises a first register, adding means for adding said first preset value with the output from said first register to supply the sum to the first register and a second register for storing a carry output from said adding means, whereby the output of said first register is output as said interpolation coefficient and the output of said second register is output as a signal for controlling said memory means and the line memory.

8. The television receiver according to claim 7, characterized in that said vertical enlargement control means (110) includes vertical position generating means for generating the value in accordance with the vertical position and value converting means for consecutively converting the output from said vertical position generating means and for outputting the converted value as said first preset value, so as to partially change the magnification rate of said image in a vertical direction.

9. The television receiver according to claim 4, 5 or 6, characterized in that said horizontal enlargement control means comprises a first register, adding means for adding said second preset value with the output from said first register to supply the sum to said first register and a second register for storing a carry output from said adding means, whereby the output of said first register is output as said interpolation coefficient and the output of said second register is output as a signal for controlling said memory means and the pixel delay means.

10. The television receiver according to claim 9, characterized in that said horizontal enlargement control means includes horizontal position generating means for generating the value in accordance with the horizontal position and value converting means for consecutively converting the count output from said horizontal position generating means and for outputting the converted value as said second preset value, so as to partially change the magnification rate of said image in a horizontal direction.

11. The television receiver according to one of claims 1 and 2 for displaying an image on a screen of a display means. characterized in that it comprises deflecting means (906, 907) for generating a deflection current for driving said display means (902); and
said enlargement control means is a correcting means (908, 909) for correcting said deflection current generated by said deflecting means, which is capable of changing the amount of the correction of said deflection current, so as to change a rate of compression/enlargement of the image displayed on the screen of said display means for each area of the screen by changing the amount of correction in said correcting means in accordance with a preset value.

12. The television receiver according to claim 11, characterized in that said deflecting means (906, 907) is capable of changing the amount of the generated deflection current and is capable of changing the compression/magnification factor of the whole of an image to by displayed on the screen of said display means by changing the amount of current in said correcting means (908, 909) depending upon the preset value.

13. The television receiver according to claim 11, characterized in that said correcting means is capable of changing only the amount of correction of a vertical deflection current for the amount of correction of said deflection current.

14. The television receiver according to claim 12, characterized in that said deflecting means is capable of changing only the amount of a vertical deflection current for the amount of correction of said deflection current.

15. The television receiver according to one of the claims 11 to 14, characterized in that said preset value is determined by depending upon an aspect ratio of an image represented by a video signal input by said display means.

Ansprüche

1. Fernsehempfänger, aufweisend:
Vergrößerungssteuermittel (110, 113; 908, 909), um ein Eingabebild um Vertikal- und/oder Horizontal-Vergrößerungsfaktoren, beziehungsweise in beide vertikale und/oder horizontale Richtungen auf eine gewünschte Größe zu komprimieren oder zu vergrößern, um es an das Längenverhältnis einer Darstellungsvorrichtung anzupassen,
dadurch gekennzeichnet, daß
das Vergrößerungssteuermittel angepaßt ist, um vertikale und/oder horizontale Vergrößerungsfaktoren, welche in verschiedenen Bereichen des Bildes in vertikaler und horizontaler Richtung variieren, anzuwenden.

2. Fernsehempfänger nach Anspruch 1, dadurch gekennzeichnet, daß das Horizontal- und Vertikal-Vergrößerungsmittel gleiche Vergrößerungsfaktoren auf einen zentralen Bereich des Bildes anwendet.

3. Fernsehempfänger nach einem der vorangehenden Ansprüche, dadurch gekennzeichnet, daß er aufweist:

ein Speichermittel (103) mit einer Speicherkapazität nicht unter einem gegebenen Wert, der mindestens mit einer Zeilenperiode gesteuert wird,

ein Takterzeugungsmittel (119) zum Erzeugen eines Lesetaktes, der eine Frequenz hat, die nicht geringer ist als die eines Schreibtaktes des Schreibtaktgebers, um ein Videosignal in das Speichermittel (103) zu schreiben und um einen Lesetakt auszugeben, um das geschriebene Videosignal von dem Speichermittel (103) zu lesen,

dadurch gekennzeichnet, daß

das Vergrößerungssteuermittel (110) ein Vertikal-Vergrößerungssteuermittel aufweist, um ein Signal zur Steuerung des Speichermittels (103) zu erzeugen und auszugeben, um wiederholt dieselbe Zeile mit einer Zeilenperiode zu lesen, die von einem ersten voreingestellten Wert abhängt, wenn das Videosignal von dem Speichermittel (103) ausgelesen wird, und

ein Horizontal-Vergrößerungssteuermittel (113), um ein Signal zur Steuerung des Speichermittels (103) zu erzeugen und auszugeben, um wiederholt dasselbe Pixel des Speichermittels (103) mit einer vorbestimmten Pixelperiode zu lesen, die von einem zweiten voreingestellten Wert abhängt, wenn das Videosignal von dem Speichermittel gelesen wird, und

daß es weiter ein Verbindungsmittel (122) aufweist, um das Ausgabesignal von dem Vertikal-Vergrößerungssteuermittel, das Ausgabesignal von dem Horizontal-Vergrößerungssteuermittel und den Lesetakt von dem Takterzeugungsmittel zu verbinden und um dem Speichermittel ein kombiniertes Signal zu liefern; um ein Videosignal zu liefern, welches ein, in horizontalen und vertikalen Richtungen, auf eine gewünschte Größe komprimiertes Bild wie ein von dem Speichermittel gelesenes Videosignal darstellt.

4. Fernsehempfänger nach Anspruch 3, dadurch gekennzeichnet, daß das Vertikal-Vergrößerungssteuermittel (110) einen Interpolationskoeffizienten erzeugt und ausgibt, der von dem ersten voreingestellten Wert abhängt und auch vom Signal zur Steuerung des Speichermittels, das Horizontal-Vergrößerungssteuermittel einen Interpolationskoeffizienten erzeugt und ausgibt, der von dem zweiten voreingestellten Wert und auch vom Signal zur Steuerung des Speichermittels abhängt, wobei ferner in einer darauffolgenden Stufe des Speichermittels (103) aufgewiesen wird:

ein Zeilenspeicher (104), um das von dem Speichermittel gelesene Videosignal um eine Zeile zu verzögern und auszugeben, wobei der Betrieb des Zeilenspeichers entsprechend dem Ausgabesignal von dem Vertikal-Vergrößerungssteuermittel gesteuert wird,

ein Vertikal-Interpolationsmittel (106), um ein Interpolationssignal entsprechend einer Interpolationskoeffizientenausgabe von dem Vertikal-Vergrößerungssteuermittel zu erzeugen und auszugeben, wobei das von dem Speichermittel gelesene Videosignal und das Ausgabesignal vom Zeilenspeicher benutzt werden,

Verzögerungsmittel (116, 117), um das Signal und die Interpolationskoeffizientenausgabe von dem Horizontal-Vergrößerungssteuermittel zu verzögern und auszugeben,

ein Pixel-Verzögerungsmittel (108), um das Ausgabesignal des Vertikal-Interpolationsmittels zu verzögern und auszugeben, wobei der Betrieb des Pixel-Verzögerungsmittels entsprechend dem Ausgabesignal von dem Verzögerungsmittel (116) gesteuert wird, und

ein Horizontal-Interpolationsmittel (109), um ein Interpolationssignal entsprechend der Interpolationskoeffizientenausgabe des Verzögerungsmittels (117) zu erzeugen und auszugeben, wobei die Ausgabesignale von dem Vertikal-Interpolationsmittel und dem Pixel-Verzögerungsmittel benutzt werden.

5. Fernsehempfänger nach Anspruch 3, dadurch gekennzeichnet, daß das Vertikal-Vergrößerungssteuermittel (110) einen Interpolationskoeffizienten erzeugt und ausgibt, der von dem ersten voreingestellten Wert und auch vom Signal zur Steuerung des Speichermittels abhängt, das Horizontal-Vergrößerungssteuermittel (113) einen Interpolationskoeffizienten erzeugt und ausgibt, der von dem zweiten voreingestellten Wert und auch vom Signal zur Steuerung des Speichermittels abhängt, wobei ferner in einer darauffolgenden Stufe des Speichermittels aufgewiesen wird:

ein erstes Verzögerungsmittels (116, 117), um das Signal und die Interpolationskoeffizientenausgabe von dem Horizontal-Vergrößerungssteuermittel zu verzögern und auszugeben,

ein Pixel-Verzögerungsmittel (108), um das von dem Speichermittel gelesene Videosignal um ein Pixel zu verzögern und auszugeben, wobei der Betrieb des Pixel-Verzögerungsmittels entsprechend einem Ausgabesignal von dem Verzögerungsmittel (116) gesteuert wird,

ein Horizontal-Interpolationsmittel (109), um ein Interpolationssignal entsprechend der Interpolationskoeffizientenausgabe von dem ersten Verzögerungsmittel (117) zu erzeugen und auszugeben, wobei das von dem Speichermittel gelesene Videosignal und das Ausgabesignal von dem Pixel-Verzögerungsmittel benutzt werden,

ein zweites Verzögerungsmittel (501, 502), um das Signal und die Interpolationskoeffizientenausgabe von dem Vertikal-Vergrößerungssteuermittel zu verzögern und auszugeben,

ein Zeilenspeicher (105), um das Ausgabesignal von dem Horizontal-Interpolationsmittel um eine Zeile zu verzögern, wobei der Betrieb des Zeilenspeichers entsprechend dem Ausgabesignal von dem zweiten Verzögerungsmittel (501) gesteuert wird, und

ein Vertikal-Interpolationsmittel (106), um ein Interpolationssignal entsprechend der Interpolationskoeffizientenausgabe von dem zweiten Verzögerungsmittel (502) zu erzeugen und auszugeben, wobei die Ausgabesignale von dem Horizontal-Interpolationsmittel und das Ausgabesignal vom Zeilenspeicher benutzt werden.

6. Fernsehempfänger nach Anspruch 3, dadurch gekennzeichnet, daß das Vertikal-Vergrößerungssteuermittel einen Interpolationskoeffizienten erzeugt und ausgibt, der von dem ersten voreingestellten Wert abhängt und auch vom Signal zur Steuerung des Speichermittels,

ein Zeilenspeicher (105), um das Videosignal, das von dem Speichermittel gelesen wird, um eine Zeile zu verzögern und auszugeben, wobei der Betrieb des Zeilenspeichers entsprechend dem Ausgabesignal von dem Vertikal-Vergrößerungssteuermittel gesteuert wird,

ein Vertikal-Interpolationsmittel (106), um ein Interpolationssignal entsprechend der Interpolationskoeffizientenausgabe von dem Vertikal-Vergrößerungssteuermittel zu erzeugen und auszugeben, wobei das von dem Speichermittel gelesene Videosignal und das Ausgabesignal vom Zeilenspeicher benutzt werden,

ein Verzögerungsmittel (116, 117), um das Signal und die Interpolationskoeffizientenausgabe von dem Horizontal-Vergrößerungssteuermittel zu verzögern und auszugeben,

ein Pixel-Verzögerungsmittel (108), um das Ausgabesignal von dem Vertikal-Interpolationsmittel zu verzögern und auszugeben, wobei der Betrieb des Pixel-Verzögerungsmittels entsprechend dem Ausgabesignal von dem Verzögerungsmittel gesteuert wird,

ein zweites Horizontal-Vergrößerungssteuermittel, um ein Signal zur Steuerung des Pixel-Verzögerungsmittels in Intervallen einer Pixelperiode entsprechend dem zweiten voreingestellten Wert zu erzeugen und auszugeben, und um einen Interpolationskoeffizienten entsprechend dem zweiten vorbestimmten Wert zu erzeugen und auszugeben, und

ein Horizontal-Interpolationsmittel (109), um ein Interpolationssignal entsprechend der Interpolationskoeffizientenausgabe von dem Verzögerungsmittel zu erzeugen und auszugeben, wobei Ausgabesignale von dem Vertikal-Interpolationsmittel und dem Pixel-Verzögerungsmittel benutzt werden.

7. Fernsehempfänger nach Ansprüchen 4, 5 oder 6, dadurch gekennzeichnet, daß das Vertikal-Vergrößerungssteuermittel ein erstes Register, ein Addierungsmittel, um den ersten vorbestimmten Wert zu der Ausgabe des ersten Registers zu addieren, um die Summe dem ersten Register zu liefern, und ein zweites Register zum Speichern einer Übertragsausgabe von dem Addierungsmittel aufweist, wobei die Ausgabe des ersten Registers eine Ausgabe ist, wie der Interpolationskoeffizient und die Ausgabe des zweiten Registers eine Ausgabe ist, wie ein Signal zur Steuerung des Speichermittels und des Zeilenspeichers.

8. Fernsehempfänger nach Anspruch 7, dadurch gekennzeichnet, daß das Vertikal-Vergrößerungssteuermittel (110) ein Vertikal-Positionserzeugungsmittel aufweist, um den Wert entsprechend der vertikalen Position zu erzeugen und ein Wert-Konvertiermittel, um hintereinander die Ausgabe des Vertikal-Positionserzeugungsmittels umzuwandeln und um den umgewandelten Wert als ersten vorbestimmten Wert auszugeben, um partiell die Vergrößerungsrate des Bildes in vertikaler Richtung zu verändern.

9. Fernsehempfänger nach Ansprüchen 4, 5, 6, dadurch gekennzeichnet, daß das Horizontal-Vergrößerungssteuermittel ein erstes Register, ein Addierungsmittel, um den zweiten vorbestimmten Wert zu der Ausgabe des ersten Registers zu addieren, um die Summe dem ersten Register zu liefern, und ein zweites Register zum Speichern einer Übertragsausgabe von dem Addierungsmittel aufweist, wobei die Ausgabe des ersten Registers eine Ausgabe ist, wie der Interpolationskoeffizient, und die Ausgabe des zweiten Registers eine Ausgabe ist, wie ein Signal zur Steuerung des Speichermittels und des Pixel-Verzögerungsmittels.

10. Fernsehempfänger nach Anspruch 9, dadurch gekennzeichnet, daß das Horizontal-Vergrößerungssteuermittel ein Horizontal-Positionserzeugungsmittel aufweist, um den Wert entsprechend der horizontalen Position zu erzeugen, und ein Wert-Konvertiermittel, um hintereinander die Zählstandausgabe des Horizontal-Positionserzeugungsmittels umzuwandeln und um den umgewandelten Wert als zweiten vorbestimmten Wert auszugeben, um partiell die Vergrößerungsrate des Bildes in horizontaler Richtung zu verändern.

11. Fernsehempfänger nach einem der Ansprüche 1 und 2 zur Darstellung eines Bildes auf einem Bildschirm eines Darstellungsmittels, dadurch gekennzeichnet, daß er Ablenkmittel (906, 907) aufweist, um einen Ablenkstrom zum Betrieb des Darstellungsmittels (902) zu erzeugen, und
das Vergrößerungssteuermittel ein Korrekturmittel (908, 909) zum Korrigieren des durch das Ablenkmittel erzeugten Ablenkstromes ist, welches fähig ist, den Korrekturbetrag des Ablenkstromes zu ändern, um eine Rate der Kompression/Vergrößerung des auf dem Bildschirm des Darstellungsmittels dargestellten Bildes, für jeden Bereich des Schirmes, durch Verändern des Korrekturbetrages in dem Korrekturmittel, entsprechend einem vorbestimmten Wert, zu ändern.

12. Fernsehempfänger nach Anspruch 11, dadurch gekennzeichnet, daß das Ablenkmittel (906, 907) fähig ist, den Betrag des erzeugten Ablenkstromes zu verändern und fähig ist, den Kompressions-/Vergrößerungsfaktor eines Ganzen des auf dem Bildschirm des Darstellungsmittels darzustellenden Bildes, durch Verändern des Strombetrages in dem Korrekturmittel (908, 909) in Abhängigkeit von dem vorbestimmten Wert, zu verändern.

13. Fernsehempfänger nach Anspruch 11, dadurch gekennzeichnet, daß das Korrekturmittel fähig ist, nur den Korrekturbetrag des vertikalen Ablenkstromes als Korrekturbetrag des Ablenkstromes zu verändern.

14. Fernsehempfänger nach Anspruch 12, dadurch gekennzeichnet, daß das Ablenkmittel fähig ist, nur den Betrag eines vertikalen Ablenkstromes als Korrekturbetrag des Ablenkstromes zu verändern.

15. Fernsehempfänger nach einem der Ansprüche 11 bis 14, dadurch gekennzeichnet, daß der vorbestimmte Wert durch seine Abhängigkeit von einem durch die Videosignaleingabe des Darstellungsmittels dargestellten Bild bestimmt wird.

Revendications

1. Récepteur de télévision comportant :
   des moyens de commande d'agrandissement (110, 113 ; 908, 909) pour comprimer ou agrandir une image d'entrée en utilisant des facteurs de grossissement vertical et/ou horizontal, respectivement, afin de lui donner une taille voulue dans la direction verticale et/ou horizontale, de manière à obtenir le même rapport d'aspect que celui d'un dispositif d'affichage,
   caractérisé en ce que
   les moyens de commande d'agrandissement sont adaptés pour appliquer des facteurs de grossissement vertical et/ou horizontal qui varient dans des zones différentes de l'image dans les directions verticale et horizontale, respectivement.

2. Récepteur de télévision selon la revendication 1, caractérisé en ce que les moyens d'agrandissement horizontal et vertical appliquent des facteurs de grossissement égaux sur une zone centrale de l'image.

3. Récepteur de télévision selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il comporte :

des moyens de mémoire (103) possédant une capacité de mémorisation non-inférieure à une valeur donnée qui est commandée en association avec au moins une période de ligne,

des moyens générateurs d'horloge (119) pour générer une horloge de lecture possédant une fréquence non-inférieure à celle d'une horloge d'écriture à partir de l'horloge d'écriture pour écrire un signal vidéo dans lesdits moyens de mémoire (103) et pour délivrer en sortie une horloge de lecture pour lire ledit signal vidéo écrit à partir desdits moyens de mémoire,

   caractérisé en ce que

lesdits moyens de commande d'agrandissement (110) comportent des moyens de commande d'agrandissement vertical pour générer et délivrer en sortie un signal destiné à commander lesdits moyens de mémoire (103) afin de lire d'une manière répétée la même ligne avec une période de ligne dépendant d'une première valeur préétablie lorsque ledit signal vidéo est lu à partir desdits moyens de mémoire (103),

et des moyens de commande d'agrandissement horizontal (113) pour générer et délivrer en sortie un signal destiné à commander lesdits moyens de mémoire (103) afin de lire d'une manière répétée le même pixel à partir desdits moyens de mémoire (103) avec une période de pixel prédéterminée dépendant d'une seconde valeur préétablie lorsque ledit signal vidéo est lu à partir desdits moyens de mémoire, et

en ce qu'il comporte en outre des moyens de combinaison (122) pour combiner le signal de sortie desdits moyens de commande d'agrandissement vertical, le signal de sortie desdits moyens de commande d'agrandissement horizontal et l'horloge de lecture desdits moyens générateurs d'horloge et pour envoyer vers lesdits moyens de mémoire un signal combiné, afin de fournir un signal vidéo représentant une image qui est comprimée et agrandie dans les directions horizontale et verticale à une taille voulue comme signal vidéo lu à partir desdits moyens de mémoire.

4. Récepteur de télévision selon la revendication 3, caractérisé en ce que lesdits moyens de commande d'agrandissement vertical (110) génèrent et délivrent en sortie un coefficient d'interpolation dépendant de ladite première valeur préétablie, ainsi que le signal pour commander lesdits moyens de mémoire, lesdits moyens de commande d'agrandissement horizontal génèrent et délivrent en sortie un coefficient d'interpolation dépendant de ladite seconde valeur préétablie, ainsi que le signal pour commander lesdits moyens de mémoire,

comportant en outre, au niveau de l'étage suivant desdits moyens de mémoire (103) :

une mémoire de ligne (104) pour retarder de une ligne ledit signal vidéo lu à partir desdits moyens de mémoire et pour le délivrer en sortie, le fonctionnement de ladite mémoire de ligne étant commandé conformément au signal de sortie desdits moyens de mémoire d'agrandissement vertical,

des moyens d'interpolation verticale (106) pour générer et délivrer en sortie un signal d'interpolation conformément à un coefficient d'interpolation délivré en sortie par lesdits moyens de commande d'agrandissement vertical par l'utilisation dudit signal vidéo lu à partir desdits moyens de mémoire et du signal de sortie délivré par ladite mémoire de ligne,

des moyens de retardement (116, 117) pour retarder et délivrer en sortie le signal et le coefficient d'interpolation délivrés en sortie par lesdits moyens de commande d'agrandissement horizontal,

des moyens de retardement de pixel (108) pour retarder le signal de sortie desdits moyens d'interpolation verticale et pour le délivrer en sortie, le fonctionnement desdits moyens de retardement de pixel étant commandé conformément au signal de sortie desdits moyens de retardement (116), et

des moyens d'interpolation horizontale (109) pour générer et délivrer en sortie un signal d'interpolation conformément au coefficient d'interpolation délivré en sortie par lesdits moyens de retardement (117) par l'utilisation des signaux de sortie desdits moyens d'interpolation verticale et desdits moyens de retardement de pixel.

5. Récepteur de télévision selon la revendication 3, caractérisé en ce que lesdits moyens de commande d'agrandissement vertical (110) génèrent et délivrent en sortie un coefficient d'interpolation dépendant de ladite première valeur préétablie, ainsi que le signal pour commander lesdits moyens de mémoire, lesdits moyens de commande d'agrandissement horizontal (113) génèrent et délivrent en sortie un coefficient d'interpolation dépendant de ladite seconde valeur préétablie, ainsi que le signal pour commander lesdits moyens de mémoire,

comportant en outre, au niveau de l'étage suivant desdits moyens desdits moyens de mémoire :

des premiers moyens de retardement (116, 117) pour retarder et délivrer en sortie le signal et le coefficient d'interpolation délivrés par lesdits moyens de commande d'agrandissement horizontal,

des moyens de retardement de pixel (108) pour retarder de un pixel ledit signal vidéo lu à partir desdits moyens de mémoire et pour le délivrer en sortie, le fonctionnement desdits moyens de retardement de pixel étant commandé conformément à un signal de sortie délivré par lesdits moyens de retardement (116),

des moyens d'interpolation horizontale (109) pour générer et délivrer en sortie un signal d'interpolation conformément au coefficient d'interpolation délivré en sortie par lesdits premiers moyens de retardement (117) par l'utilisation dudit signal vidéo lu à partir des moyens de mémoire et du signal de sortie desdits moyens de retardement de pixel,

des seconds moyens de retardement (501, 502) pour retarder et délivrer en sortie le signal et le coefficient d'interpolation délivrés en sortie par lesdits moyens de commande d'agrandissement vertical,

une mémoire de ligne (105) pour retarder de une ligne le signal de sortie délivré par lesdits moyens d'interpolation horizontale, le fonctionnement de ladite mémoire de ligne étant commandé conformément au signal de sortie desdits seconds moyens de retardement (501), et

des moyens d'interpolation verticale (106) pour générer et délivrer en sortie un signal d'interpolation conformément au coefficient d'interpolation délivré en sortie par lesdits seconds moyens de retardement (502) par l'utilisation des signaux de sortie délivrés par lesdits moyens d'interpolation horizontale et du signal de sortie délivré par ladite mémoire de ligne.

6. Récepteur de télévision selon la revendication 3, caractérisé en ce que lesdits moyens de commande d'agrandissement vertical génèrent et délivrent en sortie un coefficient d'interpolation dépendant de ladite première valeur préétablie, ainsi que le signal pour commander lesdits moyens de mémoire,

une mémoire de ligne (105) pour retarder de une ligne ledit signal vidéo lu à partir desdits moyens de mémoire et pour le délivrer en sortie, le fonctionnement de ladite mémoire de ligne étant commandé conformément au signal de sortie desdits moyens de commande d'agrandissement vertical,

des moyens d'interpolation verticale (106) pour générer et délivrer en sortie un signal d'interpolation conformément à un coefficient d'interpolation délivré en sortie par lesdits moyens de commande d'agrandissement vertical par l'utilisation dudit signal vidéo lu à partir desdits moyens de mémoire et du signal de sortie délivré par ladite mémoire de ligne,

des moyens de retardement (116, 117) pour retarder et délivrer en sortie le signal et le coefficient d'interpolation délivrés en sortie par lesdits moyens de commande d'agrandissement horizontal,

des moyens de retardement de pixel (108) pour retarder le signal de sortie desdits moyens d'interpolation verticale et pour le délivrer en sortie, le fonctionnement desdits moyens de retardement de pixel étant commandé conformément au signal de sortie desdits moyens de retardement,

des seconds moyens de commande d'agrandissement horizontal pour générer et délivrer en sortie un signal pour commander lesdits moyens de retardement de pixel à des intervalles de une période de pixel correspondant à ladite seconde valeur préétablie et pour générer et délivrer en sortie un coefficient d'interpolation correspondant à ladite seconde valeur préétablie, et

des moyens d'interpolation horizontale (109) pour générer et délivrer en sortie un signal d'interpolation conformément au coefficient d'interpolation délivré en sortie par lesdits moyens de retardement par l'utilisation des signaux de sortie desdits moyens d'interpolation verticale et desdits moyens de retardement de pixel.

7. Récepteur de télévision selon la revendication 4, 5 ou 6, caractérisé en ce que lesdits moyens de commande d'agrandissement vertical comportent un premier registre, des moyens d'addition pour additionner ladite première valeur préétablie avec la sortie dudit premier registre afin d'envoyer la somme vers le premier registre et un second registre pour mémoriser une sortie de report provenant desdits moyens d'addition, la sortie dudit premier registre étant délivrée en sortie comme coefficient d'interpolation et la sortie dudit second registre étant délivrée en sortie comme signal pour commander lesdits moyens de mémoire et la mémoire de ligne.

8. Récepteur de télévision selon la revendication 7, caractérisé en ce que lesdits moyens de commande d'agrandissement vertical (110) comportent des moyens générateurs de position verticale pour générer la valeur conformément à la position verticale et des moyens de conversion de valeur pour convertir consécutivement la sortie desdits moyens générateurs de position verticale et pour délivrer en sortie la valeur convertie comme première valeur préétablie, de manière à modifier partiellement le coefficient de grossissement de ladite image dans une direction verticale.

9. Récepteur de télévision selon la revendication 4, 5 ou 6, caractérisé en ce que lesdits moyens de commande d'agrandissement horizontal comportent un premier registre, des moyens d'addition pour additionner ladite seconde valeur préétablie avec la sortie dudit premier registre pour envoyer la somme vers ledit premier registre et un second registre pour mémoriser une sortie de report desdits moyens d'addition, la sortie dudit premier registre étant délivrée en sortie comme coefficient d'interpolation et la sortie dudit second registre étant délivrée en sortie comme signal pour commander lesdits moyens de mémoire et les moyens de retardement de pixel.

10. Récepteur de télévision selon la revendication 9, caractérisé en ce que lesdits moyens de commande d'agrandissement horizontal comportent des moyens générateurs de position horizontale pour générer la valeur conformément à la position horizontale et des moyens de conversion de valeur pour convertir consécutivement la sortie desdits moyens générateurs de position horizontale et pour délivrer en sortie la valeur convertie comme seconde valeur préétablie, de manière à modifier partiellement le coefficient de grossissement de ladite image dans une direction horizontale.

11. Récepteur de télévision selon l'une quelconque des revendications 1 à 2, pour afficher une image sur un écran de moyens d'affichage, caractérisé en ce qu'il comporte des moyens de déflexion (906, 907) pour générer un courant de déflexion destiné à commander lesdits moyens d'affichage (902), et
   lesdits moyens de commande d'agrandissement sont des moyens de correction (908, 909) pour corriger ledit courant de déflexion généré par lesdits moyens de déflexion, qui sont capables de modifier la quantité de correction dudit courant de déflexion, de manière à modifier un coefficient de compression/agrandissement de l'image affichée sur l'écran desdits moyens d'affichage pour chaque zone de l'écran en modifiant la quantité de correction dans lesdits moyens de correction conformément à une valeur préétablie.

12. Récepteur de télévision selon la revendication 11, caractérisé en ce que lesdits moyens de déflexion (906, 907) sont capables de modifier la quantité de courant de déflexion généré et sont capables de modifier le facteur de compression/agrandissement de la totalité d'une image affichée sur l'écran desdits moyens d'affichage en modifiant la quantité de courant dans lesdits moyens de correction (908, 909) suivant la valeur préétablie.

13. Récepteur de télévision selon la revendication 11, caractérisé en ce que lesdits moyens de correction sont capables de ne modifier que la quantité de correction d'un courant de déflexion vertical pour la quantité de correction dudit courant de déflexion.

14. Récepteur de télévision selon la revendication 12, caractérisé en ce que lesdits moyens de déflexion sont capables de ne modifier que la quantité d'un courant de déflexion vertical pour la quantité de correction dudit courant de déflexion.

15. Récepteur de télévision selon l'une quelconque des revendications 11 à 14, caractérisé en ce que ladite valeur préétablie est déterminée en fonction d'un rapport d'aspect d'une image représentée par un signal vidéo entré par lesdits moyens d'affichage.

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